The first type of architectures aim to use a division of labor between Gaussian and non-Gaussian resources (see tab:gaussian).
The Gaussian resource is provided by easy-to-generate CV cluster states, which are multi-mode Gaussian states [1]}.
There has been substantial progress in designing and deterministically generating CV cluster states in one [2]}, [3]}, [4]}, two [5]}, [6]}, [7]}, [8]}, [9]}, and higher dimensions [10]}, [11]}, [12]}.
In each of these architectures, the quantum information is encoded in a bosonic qubit introduced by Gottesman, Kitaev and Preskill (GKP) [13]}.
Clifford circuits—which make up the majority of operations required for a fault-tolerant quantum computer—can be implemented via measurement-based quantum computation (MBQC) on the CV cluster state.
By circumventing the need for an entangled resource state made entirely out of encoded qubits (as required by the second class of architectures), this approach partially alleviates the burden on the GKP state sources.
However, a truly regular supply of GKP encoded states is still required; they provide the necessary non-Gaussianity, implement non-Clifford gates, and correct CV errors.
Thus far, prior work has required that such qubits can be supplied and coupled to the cluster state deterministically at regular intervals.
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